Processes and facilities for the continuous coating of workpieces have been proposed in U.S. Pat. Nos. 4,549,866; 4,588,605, as well as 4,661,379. Other processes and facilities of the aforementioned type have been proposed in U.S. Pat. Nos. 3,526,027; 2,974,060; 3,077,171; 3,208,868; 3,394,450; 3,678,336; 3,840,138 and 4,098,226; European Laid-Open Applications 93,083; 132,229 and 160,886; as well as DOS 2,724,031.
It is furthermore known to coat workpieces, such as metal can bodies, with powder as the coating medium, for example, along their inner longitudinal weld seam. In this process, such can bodies are moved over a working arm from which powder is sprayed toward the zone to be coated. Customarily, the adhesion of the powder to the can body is electrostatically enhanced in this procedure by producing a high electrostatic field in the spray region and by charging the powder so that the force of the field urges the powder against the can body or the workpiece and retains the powder at those places. Subsequently to this powder coating step, the workpieces, and specifically the aforementioned can bodies, are moved through a long heating station having a length of several meters where the adhered powder is heated to such an extent that it forms a protective film in the coated zone. The length of the above-mentioned heating station depends on the transit velocities of such workpieces and has a length, as mentioned above, of several meters. This is a disadvantage from the viewpoints of the space required for such installations and the structural expenditure.